Truck hoist



Sept. l2, 1967 H. T. WICKLUND TRUCK HOIST 4 Sheets-Sheet l Filed July G,1965 FTTYIS.

sept. 12, 1967 H. T. WICKLUND 3,341,038

TRUCK HOIST Filed July 6, 1965- 4 Sheets-Sheet 2 INVENTOR HH BOLD 7.W/CKLUND Sept. 1.2, 1967 H. T. WICKLUND 3,341,038

TRUCK HOIST Filled July i), 1965 4 Sheets-Sheet 3 Sept- 12, 1957 H. T.WICKLUND 3,341,038

TRUCK HOIST Filed July 1965 4 Sheets-Sheet 4 -ls- E INVENTOR #HRC/.0 T.WICKLUND v HTTYS.

United States Patent l 3,341,038 TRUCK HOIST Harold T. Wicklund, 1520 S.6th West, Missoula, Mont. 59801 Filed July 6, 1965, Ser. No. 469,636 10Claims. (Cl. 214-75) This invention relates to a novel hoist for use inconjunction with a truck.

There are many instances when it is desirable or necessary to utilize amechanical hoist to assist in loading and unloading articles in relationto a truck, where the article must be lifted at the rear of the truckand placed at its desired location thereon. Many mechanical devices havebeen previously mounted on trucks to accomplish this purpose, but thesehave either been restricted to a stationary location on the truck or, ifmovable, have been quite bulky permanent additions to the truck itself.'Ihe present invention provides a simple attachment that can be mountedon any truck to provide a portable hoist capable of reaching rearwardlyfrom the truck and capable of positioning articles in the truck at anydesired location.

It is a first object of this invention to provide such a hoist that ismechanically simple in structure. My preferred embodiment utilizes anarched design, incorporating high strength along with the simplicity ofstructure required.

Another object of this invention is to provide a hoist structure thatwill straddle the bed of a truck, providing no obstruction to normal useof the truck bed. It is capable of moving over articles positioned onthe truck Without Clisturbing them.

Another object of this invention is to provide an adjustable hoist,straddling above the truck bed and capable of bkeing adjusted in widthto iit any reasonable size of truc These and further objects will beevident from the following disclosure, taken together with ,theaccompanying drawings, which illustrate a preferred form of theinvention. It is to be understood that this form of the invention is notto limit or restrict the scope of the invention, which 1s set out in thefollowing claims.

In the drawings:

FIGURE 1 is a side view of a truck equipped with the present hoist, thehoist being shown in full lines at a location adjacent to the truck caband with the load in an elevated position, the hoist being .illustratedin dashed lines at the rear of thetruck bed with the hoist shown in alowered condition;

FIGURE 2 is a rear sectional view taken along line 2 2 in FIGURE 1 at anenlarged scale;

FIGURE 3 is an enlarged fragmentary top view of the hoist shown inFIGURE l;

FIGURE 4 is a front sectional view taken along line 4 4 in FIGURE 1 atan enlarged scale;

FIGURE Sis an enlarged fragmentary sectional view t-aken along line 5 5in FIGURE 2;

FIGURE 6 is an enlarged fragmentary sectional View taken along line 6 6in FIGURE 5;

FIGURE 7 is an enlarged fragmentary sectional view taken along line 7 7in FIGURE 2; and

FIGURE 8 is a diagram showing the force relationship that exists on theboom during movement thereof -about its axis.

FIGURES 1 through 4 show the general arrangement of the hoist with whichthis specification is concerned. The hoist is shown mounted at the rearof a truck 10 of conventional construction. It is to be emphasized thatYthe structure of truck 10 need not be modied in any manner in order toutilize this hoist apparatus. The hoist is mounted on the box 11 oftruck 10, which is illustrated as a pick-up truck, but the hoist also isequally applicable to a dat bed truck or any other conventional type ofopen storage compartment on a truck or other platform.

'I`=he hoist itself comprises a pair of rails 12, a boom support 15 anda boom 23. These basic elements cooperate to guide ya cable 37 on whichthe actual load 53 is carried.

Rails 12 are simply two I-'beams transversely located on the rear oftruck 10 and fastened by means of mounting brackets 13 that support andgrip the lower portion of each rail 12. The mounting brackets 13 areprovided with stems 14 (FIGURE 2) which fit into the conventional stakepockets along the sides of truck 10.

The boom support 15 rises from legs 16 made of tubular material havingsuitable strength characteristics. The upright legs 16 are carried by ahorizontal T-shaped bar 18 at each .side of the apparatus (FIGURE 1).The ends of the T-shaped bar 18 are fixed to roller brackets 17 thatcarry lower rollers 20. Rollers 20 ride along the lower surfaces of therails 12 and serve to guide the hoist for longitudinal movement relativeto the bed of truck 10.

The rear ends of the T-shaped bars 18 at the respective re-ar rollerbrackets 17 are structurally joined to the upper ends of the legs 16 bymeans of tubular braces 21. The upper end of each brace 21 carries anintegral bracket 22 which in turn is fixed relative to the respectiveleg 16 at each side of the structure. The precise connection will bedescribed below. The boom support 15 is cornpleted by complementaryarched support sections 25 that are joined at the center of thestructure to produce an integral assembly that has a constant uprightorientation relative to the load supporting bed of truck 10 regardlessof its longitudinal position thereon.

The boom 23 is also formed in an arch configuration. It is mounted onhorizontal support braces 24 at each side of the boom support 15. Thepivotal axis of the boom 23 is indicated as 26 (FIGURE 1), being ahorizontal transverse axis on boom support 15. Boom 23 also includesstraight legs 27 at each of its sides and arched sections 28 that arejoined at a central sheave block 30. The boom 23 is located outside ofthe arch formed by the boom support 15. The sheave block 30 includes arotatable guide pulley 31 for the supporting load cable.

Mounted at the center of boom support 15 directly beneath the connectionbetween the two arched support sections 25 is a central guide pulley 32carried by a universal bracket assembly 33 lwhich permits the pulley 32to pivot to any required angular orientation. A side pulley 34, rotatedabout a longitudinal axis, is iixed to the boom support 15 (FIGURES 2and 4). A cable 37 is entrained over the side pulley 34, the centralguide pulley 32 and the pulley 31 upon sheave block 30. The outer end ofcable 37 is provided With a hook 38 for engagement with a load and anenlargement 40 which cannot pass the rear surface of sheave block 30 andtherefore must engage the sheave block 30 as an abutment.

The end of the cable 37 opposite to that entrained about pulleys 31, 32and 34 is wound about a drum 3'6 on a conventional winch 35. The winch'35 can be either manually operated or motor driven.

The longitudinal position of boom support 15 relative to the box 11 oftruck 10 can be at `any desired position. Normally two locationsrequired, one at the front of the box 11, and one at the rear thereof.While a more complicated braking arrangement might be used, I have showna simple bracket 42 at the side of the T-shaped bar 18, which guides avertical pin 41 received through matching apertures in the bracket 42and the upper portion of the respective rail 12. By placing the pin 41through these apertures at either of the two positions shown in FIGURE1, the boom support 15 can be fixed relative to truck 10 so that it willnot be displaced by movement of the truck.

Patented Sept. 12, 1967 It is necessary to releasably lock the positionof the boom 23 in its upper position, shown in full lines in FIG- URES 1through 4. This is accomplished by a releasable stop mechanism shown indetails in FIGURES 5 and 6. This stop mechanism is only exemplary, andcan be replaced by any suitable stop apparatus. The illustrated exampleshows a stop 43 that is normally in the path of one of the legs 27 ofboom 23. It has an angular rear surface so that the boom 23 can passstop 43 when pivoting in a clockwise direction as seen in FIGURE 1.However, Iafter the boom 23 has passed stop 43, it will remain in itspath, blocking counter clockwise motion until stop 43 has been manuallyreleased.

The stop 43 is mounted on a pivot shaft 44 about which is wound abiasing spring 45 connected between the boom support 15 and stop 43 soas to urge stop 43 to the right as seen in FIGURES 5 and 6. The stop 43is provided wit-h a crank arm 46 located at the inner side of the leg 16on boom support 15 that carries it, connected by means of a cable 48 toan operating lever 47. Downward motion of the operating lever 47, asshown in FIGURE 1, will cause the crank 46 to be pulled to the left asseen in FIG- URES 5 and 6, thereby permitting downward movement of boom23.

The various connections between the tubular members illustrated arepreferably made by a simple cast socket assembly shown in detail inFIGURE 7. The socket 50 is suitably secured within the end of thetubular member and has two spaced ears 51 so located that ears 51 of asecond socket 50 will intermesh therewith and be joined by a lockingbolt 52. Suitable washers 54 are used to ll areas between intermeshingsockets or other brackets which are not filled by the intermeshing ears51. This socket is used between the legs and arched sections of both theboom support 15 and boom 23 and also at the central connections betweenthe arched support sections 25 and the -arched sections 28 of the boomsupport 15 and boom 23 respectively. Socket 50 is also used at the baseof the legs for the boom support 15 and a boom 23 being made tocooperate with the roller brackets 17 as can be seen in FIGURES 2 and 4.

The operation of this device is quite simple. When loading onto the bedof truck 10, the boom support 15 is positioned at the rear of the truckas shown in dashed lines in FIGURE l. Release of the operating lever 47causes the stop 43 to permit the boom 23 to be lowered -as winch 35plays out the cable 37. The horizontal limiting position of boom 23 isdefined by engagement of the boom legs 27 with the horizontal support 24on boom support 15. The load 53 can then be engaged by the hook 38 orother suitable attaching device and the winch 35 operated to raise theouter end of cable 37 Initial motion of the cable 37 will simply raisethe load, the boom 23 remaining -in its horizontal position. When theenlargement 40 at the end of cable 37 abuts the sheave block 30, furthermovement of cable 37 will cause the boom 23 to pivot in a clockwisedirection (FIGURE 1) about its pivotal axis 26. This will not only raisethe load 53 but will swing it forwardly beneath the arched boom support15. The final posit-ion of boom 23 is as shown in full lines in FIGURE1, with load 53 extending forwardly beyond the boom support 15. When theboom 23 passes stop 43, counterclockwise movement of boom 23 isprohibited until release of stop 43 by movement of operating lever 47.The pin 41 can then be released and the boom support 15 and boom 23 canbe manually or mechanically moved to the forward position shown in fulllines.

When boom support 15 .is in its forward position and locked by means ofpins 41, the load can be lowered onto the bed of truck directly beneaththe boom support 15, by simply playing out the cable 37 withoutreleasing the stop 43. Thus, this hoist permits loads to be positionedquite simply at a forward position on the truck 10.

Unloading of an article `from the truck 10 involves the reversal of themovements just described. The hoist is extremely versatile and does notobstruct the normal use of the truck. When use of the hoist is notdesired, release of the two connections between the braces 21 and theforward roller brackets 37 permits the boom support 15 and the boom 23to be pivoted forwardly after movement of the -boom support 15 to a rearpostion on the truck, so that the apparatus will lie in a lowerelevation.

In FIGURE 8 is illustrated the force relationship that exists on theboom 23 during pivotal motion of boom 23 between its horizontal positionand its upper or raised position. In this diagram, the pivot axis 26 ofthe boom 23 is related to the position of the central guide pulley 32.Six different positions of the boom 23 are indicated, each being 15degrees apart. The boorn pulley 31 is shown lat its position relative tomove the pulley 32. A first line 31 A-F indicates the line of force onthe pulley 31 and boom 23 resultant to the force applied thereto by thewinch 35 pulling on cable 37. A second line 31 G-L indicates theresultant force on pulley 31 and boom 23 due to lthe load carried by thecable 37. Since these two forces will be of equal magnitude, the arrowsindicative of the force magnitude are equal. By drawing lines parallelto these indicated forces, the resultant force on boom 23 is determined.The location of the resultant intersection -is circled in each instance.Small indicative arrows 55 are used to indicate the general directionand magnitude of the forces involved.

In order to properly utilize the boom 23, it is important that there -belittle or no upward force resultant on boom 23. If a large upward forceresults, boom 23 will swing upwardly, allowing the outer end of thecable 37 to drop. It is important that the enlargement 40 at the end ofcable 37 remain in contact with the sheave block 30 for proper loadcontrol. As shown in FIGURE 8, this can be effectively accomplished, andhas been done in actual practice, by locating the position of the boomaxis 26 to one side of a plane 57 drawn vertically through the center ofthe central guide pulley 32, and by maintaining the position of thepulley 31 at the opposite side of the plane 57. If the position of theaxis 26 approaches too close to the plane 57, the resultant upward forcewill overcome frictional forces involved in the bearings and allow theboom 23 to swing upwardly without control.

As seen in FIGURE 8, the described embodiment positions the axis 26forward of plane 57, the effective tangential radius of pulley 31relative to axis 26 being greater than the effective tangential rad-iusof pulley 32 relative to axis 26. In addition, when the radian throughthe center of pulley 31 relative to axis 26 subtends an angle of 45relative to the horizontal, the reach of cable from pulley 31 to pulley32 is horizontal.

The specific construction of the apparatus as described and shown in thedrawings is not intended to confine the limits of this invention. TheVapparatus can be made with greater reinforcing and can be made ofmaterials other than those shown, which are preferably tubular. Thedevice is adjustable by means of the sockets 50 to fit varying widths oftruck beds, but it -is to be understood that other suitable archedarrangements could be substituted in pl-ace of those illustrated.Particularly the releasable stop 43 and the braking pin 41 are onlyexamples of devices that might be used. Other equivalent structurescould easily be substituted.

Having thus described my invention, I claim:

1. In combination with a truck having a longitudinal load supportingbed; a hoist assembly comprising:

a rigid arched boom support mounted on said bed in a constant uprightorientation relative to said bed for selective movement in alongitudinal direction relative to said bed, said boom support beingtransversely oriented and extending upwardly and inwardly from bothsides thereof over the bed;

an -arched boom pivotally mounted on said boom support about atransverse axis;

a load supporting `cable guided on said boom support and by a pulley atthe center of said boom;

means on said cable selectively engageable with said boom to selectivelypivot said boom about its axis on said boom support responsive to motionof said cable;

and cable winding means on said boom support connected to said cable toselectively wind or unwind said cable.

2. In the apparatus defined in claim 1:

locking means automatically engageable between said bed and said boomsupport responsive to predetermined upward pivotal motion of said boomto limit downward motion of said boom relative to said bed.

3. A hoist apparatus for trucks, comprising:

a pair of transversely spaced longitudinal rails;

a rigid arched boom support, said support being provided with supportingroller assemblies at its lower end in engagement with the respectiverails, said boom support being transversely oriented in `a constantupright orientation and extending upwardly and inwardly from both sidestoward its center;

an arched boom pivotally mounted on said boom support about a transversepivotal axis;

`a load supporting cable having one end portion thereof guided on saidboom support and by a support pulley at the center of said boom;

means on said cable selectively engageable with said boom to pivot saidboom about its pivotal axis in response to motion of said cable;

`and a winch mounted on said boom support having the remaining endportion of said cable wrapped about the drum thereof.

4. An apparatus as defined in claim 3, wherein said cable is guided by acentr-al guide pulley at the transverse center of said boom support;

the location of said boom pivotal axis being longitudinally spaced froma vertical plane containing the pivotal axis of said central guidepulley;

the location of said support pulley on said boom being positioned at theside of said last-named plane opposite to said pivotal axis.

5. An apparatus as defined in claim 3, wherein said cable is guided by acentral guide pulley at the transverse center of said boom support;

the location of said boom pivotal axis being longitudinally spaced froma vertical plane containing the pivotal axis of said central guidepulley;

the location of said support pulley on said boom being positioned at theside of said last-named plane opposite to said pivotal axis;

and releasable stop means on said boom support engageable with said boomresponsive to predetermined upward pivotal motion of said boom toselectively prevent subsequent downward motion of said boom about itspivotal axis.

6. A hoist apparatus for trucks, comprising:

-a pair of transversely spaced longitudinal rails;

a rigid upwardly arched boom support, said support being mounted at thelower ends thereof by said4 rails in a constant upright orientation andextending transversely therebetween;

an arched boom pivotally mounted on said boom support about a transversepivotal axis;

a central guide pulley mounted at the center of said boom support;

a sheave block mounted on said boom at the center thereof, said sheaveblock including a support pulley;

a cable having one end portion guided on said boom and engaged over saidcentral guide pulley and said support pulley, the outer end of saidcable having an enlarged abutment xed thereto selectively engageablewith said sheave block;

and a winch on said boom support, said winch including a cable drumabout which is wrapped the remaining end portion of said cable.

7. An apparatus .as defined in claim 6 wherein said support pulley andsaid boom pivotal axis are located at opposite sides of a vertical planecontaining the axis of said central guide pulley.

8. In combination with a truck having a longitudinal load supportingbed, a hoist assembly comprising:

a rigid arched boom support mounted on said bed in a fixed uprightorientation, said boom support being mounted on said bed for relativelylongitudinal movement relative thereto and being transversely orientedacross said bed, said boom support including members extending upwardlyand inwardly toward the center thereof to form an unobstructed integralarch;

a pulley mounted on Inhe arch of said boom support;

an arched boom mounted on said boom support about a transverse pivotalaxis positioned forward of a vertical plane intersecting the center ofsaid pulley, said arched boom being connected to said boom support attransversely spaced positions adjacent the sides of the boom support toform an unobstructed arch;

cable guide means on said boom a winch on said boom support;

and a cable wound about said winch and extending outwardly therefrom,said cable having a portion thereof entrained about said pulley and oversaid cable guide means and having means thereon adjacent its outer endto selectively engage said cable guide means to limit further upwardmotion of the cable relative to said cable guide means following suchengagement.

9. An apparatus as set out in claim 8, wherein tlhe effective tangentialradial separation between the cable guide means and said axis is greaterthan the effective tangential separation between said pulley and saidaxis along said portion of said cable.

10. An apparatus as set out in claim 8, wherein said portion of saidcable is horizontal when a radian through the center of said cable guidemeans relative to said axis subtends an angle of 45 relative to thehorizontal.

at the center thereof;

References Cited UNITED STATES PATENTS 1,464,131 8/1923` Goodger 212-82,633,999 4/ 1953 Blackman et al. 212-8 2,911,118 11/1959 Tapp 2214--77GERALD M. FORLENZA, Primary Examiner. ROBERT G. SHERIDAN, Examiner.

1. IN COMBINATION WITH A TRUCK HAVING A LONGITUDINAL LOAD SUPPORTING BED; A HOIST ASSEMBLY COMPRISING: A RIGID ARCHED BOOM SUPPORT MOUNTED ON SAID BED IN A CONSTANT UPRIGHT ORIENTATION RELATIVE TO SAID BED FOR SELECTIVE MOVEMENT IN A LONGITUDINAL DIRECTION RELATIVE TO SAID BED, SAID BOOM SUPPORT BEING TRANSVERSELY ORIENTED AND EXTENDING UPWARDLY AND INWARDLY FROM BOTH SIDES THEREOF OVER THE BED; AN ARCHED BOOM PIVOTALLY MOUNTED ON SAID BOOM SUPPORT ABOUT A TRANSVERSE AXIS; A LOAD SUPPORTING CABLE GUIDED ON SAID BOOM SUPPORT AND BY A PULLEY AT THE CENTER OF SAID BOOM; MEANS ON SAID CABLE SELECTIVELY ENGAGEABLE WITH SAID BOOM TO SELECTIVELY PIVOT SAID BOOM ABOUT IT AXIS ON SAID BOOM SUPPORT RESPONSIVE TO MOTION OF SAID CABLE; AND CABLE WINDING MEANS ON SAID BOOM SUPPORT CONNECTED TO SAID CABLE TO SELECTIVELY WIND OR UNWIND SAID CABLE. 